Trulicity Half-Life Calculator

Trulicity is dulaglutide, with an elimination half-life of about 5 days and peak levels 24 to 72 hours, median 48 after a dose, per the FDA label. On the label schedule (a weekly injection), levels reach steady state about 4 weeks after the first dose, and after a last dose they fall below 5% of that steady level in about 3 weeks.

Between scheduled doses, levels swing between a peak and a trough of about 53% of that peak, which is why the calculator's chart looks like a sawtooth rather than a flat line. The label also reports that 47% at 1.5 mg and aboveof each dose is absorbed into circulation; the calculator's mg figures build that in.

The Trulicity label instructs that a missed dose be taken as soon as possible if at least 3 days (72 hours) remain before the next scheduled dose; otherwise skip it and resume the regular schedule.

That window is the half-life doing the work: with about 5 daysof half-life, a late dose still lands on a meaningful base. This is the label's instruction to prescribers, not our advice; if you have missed a dose, your own label and prescriber are the authority.

Trulicity follows the pattern every 5-day-half-life weekly injectable shares: a week after a dose roughly half is still on board, each new dose lands on that base, and the whole system settles into its steady rhythm after about four weekly injections. The 72-hour missed-dose window in the label is the same arithmetic expressed as a rule.

Peak levels arrive later than with tirzepatide (median 48 hours versus 24), so the day-after-injection experience differs slightly even though the weekly timeline matches.